This is a longitudinal investigation over a five-year period of two samples of Manhattan families and their children, one a random Cross- Section sample (N equals 1034) and the other a Welfare sample (N equals 1000) selected randomly from four Welfare Centers. At the five-year follow-up point, 71 percent of the Cross-Section families were interviewed and 67 percent of the Welfare sample. The study objective is to specify the relations between environmental stress and strain (as evidenced by behavioral disorders) in urban children. Specifically, the study will determine those changes in stress patterns (social- demographic, parental and parent-child factors) associated with changes in different types of behavioral impairment and will determine those child behaviors and environmental stresses predictive of long-term enduring disorder. In addition, the impact of intervening events or change relative to the impact of continuing stressful processes will be studied. Age-developmental trends of child behaviors will be analyzed. Validity tissues will be handled by comparing the same information from multiple sources - the mother, the child himself, and the school. The relative contributions of child personality and environmental stresses to school performance will be determined. Factor analysis, multiple regression, and path analysis are some data-analytic techniques used to pursue these objectives.